Examples of surprisingly high mileages given to towns on UK road signs

[Ediswan]

Meanwhile, in France, isn't "Paris" signed from virtually everywhere?!

Which, unless your origin or destination are near Paris, acts as useful 'Avoid' sign.

 

[snowball]

For some years in the 1960s Preston and Birmingham were almost the only destinations signed along the M6 (northbound and southbound respectively) at junctions anywhere between those two places.

Unless there have been changes since I was last there, you have to get a long way north of Bristol on the M5 before Birmingham is mentioned.